Radio power filter condenser



Jan. 3, 1939. P. A. TARR RADIO POWER FILTER CONDENSER Filed Nov. :14, 1936 INVENTOR. P572 A. FARR ATTORNEYS Patented Jan. a, 1939 PATENT orrics 2,142,105 asmo rowan mm oomnsaa PeterA. Tan,

Berkeley, Calif.

Application November 14, 1938, Serial No. 110,879

Claims.

This invention relates 'to electric condensers. and has for its object improvements in power filter or by-Dass condensers for A. C. radio sets whereby the capacity of the condenser may be.

easily varied between certain predetermined values, and the condenser may be easily and quickly removed or applied to the set, or the units within the condenser shell changed, without the use of toolsand the removal of wires or connections. Other objects and advantages oi the improvement will appear in the following description and accompanying drawing.

In. the drawing Fig. 1 is a vertical view of my improved condenser partly in section to show both external and internal construction ofthe outer container.

Fig. 2 is a plan view of the outer container showing three segment-shaped condenser units in place.

Fig. 3 is a perspective view of one o! the condenser units.

Fig. 4 is av plan view of an outer container with fourunit condensers in place.

Fig. 5 is a vertical sectional view of the lower part 01 the condenser assembly showing a variation in arrangement of contact elements.

Fig. 6 is a vertical cross section of the base connection plate.

Fig. 7 is an enlarged elevation partly-in section, of one of the contact prongs.

In radio sets using an A. C. power, or power pack, as the source of power for various circuits,

generally several so-called filter condensers, bias circuit condensers, or by-pass condensers of various capacities and voltage, are usedto by-' pass unwanted frequencies etc., and the various filter or by-pass condensers are generally a source of trouble as well as possible fire danger in case oi breakdowns, and as they are permanently installed units they can only be removed with considerable work and difflculty for testing or checking purposes, and hence this important attention is generally ignored by radio set owners until serious trouble develops, and even then is not easily traced by the radio repair man to the varieasily carried out.

In further detail, the drawing shows my condenser assembly to comprise an exterior casing or receptacle, I, preierably'oi' sheet metal, and which may be cylindrical or rectangular in cross section, open at the top and closed at the bottom as at Land provided with a tel....copic lid 3, also preferably of sheet metal and which is engaged :5 over the casing l as by a bayonet joint 4 or any suitable snap catch or thread as to hold the I parts together in the manner indicated in Fig. 1.

Within the casing are fixed partitions I separating the interior into three longitudinal spaces 10 in which are disposed three elongated condenser units 6, l and 8, which carry at their lower ends terminal contact buttons 9 and of the respec-- tlve condenser elements which they contain.

These condenser units t are preferably of i5 paraiiined cardboard or other suitable material, and each contains a by-pass or filter condenser assembly of any desired form, voltage, and. capacity, such as a paper condenser, dry or wet electrolytic condenser, or any other type, and for any 2!) purpose in connection with the so-called A. C.

' power-pack, or power circuit of a radio set, and with their electrical capacities and character marked on the upper ends, such as mid, 8 mid, etc., as indicated in Fig. 3, preferably also in the case of electrolytic condensers, the date of sealing or manufacture, as their electric properties depend to a certain extent on their age.

To identify the positive and negative-relation oi the terminal buttons 9 and it of the condenser units I apply diflerent colored spots on the upper end of each unit package in line with the button below as indicated by the red and black spots 9' and It in Fig. 3. The other units may have other color combinations as orange-green, white-brown, etc., so they will not get mixed, and further color identification means is used to trace the units to the contact plugs of the assemblage as will be explained.

Secured to the bottom of the casing I, either 40 inside or outside, is'a plate or disk of insulating material H from which extends downwardly a plurality of contact prongs ii, at least one or two of which, l2',-are thicker than the others so that they can only enter the larger of a similar series 0! spring grip plug-in contact sleeves It carried by a heavy insulating base plate ll shown in Fig. 6 and into which the prongs are adapted to fit.

Prongs l2 and I! pass tree or contact through so openings in the bottom 2 or the casing I, and each prong is provided at its upper end with a spring contact strip i5 arranged to contact one oi the buttons I or III oi the condenser units as showninFig.1 Iidesiredthebuttonsandss spring contact strips may be reversed in tion with respect to the prongs and the condenser units as shown at 3" and iii" in Fig. 5, but I pre fer the first way described as it makes the con denser units free of objectionable projections which might become injured in handling and storage. a

The condenser units fit freely, each within on of the compartments in the casing i, and after they are dropped in they project a distance above its own end as at X so as to be readily grasped. by the fingers for easy removal, while with-in the cover 3 of the casing is a thick block of resilient materials such as sponge rubber id or resilient felt, of such a thickness that it will be tightly compressed when the cover 3 is secured in place so that it will force a good connection with all of the contact members 9, ill, at the lower ends of the units.

When there are four or more spaces partitioned off, or where the casing is rectangular as at ill in Fig. 4, the lower end contacts of the con denser units id, is, 2i, will each be fitted with their respective terminal contacts as described for Figs. 3. and 2 at their lower ends as indicated.

The plug-in prongs it and i2 of the casing are preferably hollowedout or slightly countersunk at their lower ends as indicated at El in Fig. 7 and partially filled with. a colored enamel as at 28 corresponding to the spot of color on the upper end of the particular condenser unit treminal intended to'be connected to it for a particular assemblage, and each may thus be identified by looking at the endsof the plugs, even if plugged into the base plate id.

The lower baseplate id may be a separate plate secured to the radio set box or frame as by screws or bolts 22, or the plate may be the bottom of the chassis oi the set or wall of the radio cabinet or box itself. The various terminal sockets it will be suitably connected by wires or metal strips 23, 2 3 to effect the desired circuit or cir cults through the several condenser units, either in multiple, series, or any other way to any of the elements of the set desired, and all circuits may be completed by simply plugging in the casing i, its one or two extra thick prongs i2 insuring against wrong connections. Where required, two or more casings of condenser units may be used in a radioset.

When the casing i is plugged into the base plate it a. resilient metal strip 25. extending upward from one or more of the screws 22 which may be grounded as indicated at when in the set, to thus effectually shield the assembly.

By the construction above described, various combinations of units of different capacity, voltage, or electrical properties may be readily made, or any desired circuits either in series or parallel may be had, depending on the connections below the base plate and the number and capacity of the interchangeable units inserted in the receptacle l, as there may be one 8 and two 4 mid. units,

2,lid2,70d v or three is, three 8s, two 8s and one 4, etc., or

one orrnore of the compartments may be left open, or a unit reversed if not wanted, or specialunits of any capacity voltage or nature inserted. Also, the whole assembly may be instantly removed from the set for testing and a temporary assembly plugged in-without losing more than a moment's use of the set, or any one of the units may be instantly removed and another one dropped into 318.06.

My use of the term power filter condenser" in the claims is to be understood as embracing any type of condenser used in the various power circuits of radio apparatus.

Having thus described my improved filter condenser assemhlage, what 1 claim is:

1. A power filter condenser comprising a casing provided with contact plug-in terminals at one end and a removable cover at the opposite ends. plurality of condenserunits arranged side by side and each separately removably positioned within said casing, each of said units provided with exposed contact terminals arranged to make circuit contacts with said plug-in terminals of the casing when inserted therein and said plug-in terminals of the casing arranged for plugging 7 into a terminal socket plate.

2. A power filter condenser comprising a casing provided with contact plug-in terminals at one end and a removable cover at the opposite said cover arranged to extend over and enclose the projecting ends of said' units, each of said said plug-in terminals of the casing arranged for plugging one way only into a terminal socket plate.

3. In the construction specified in claim 1, partitlons Within said casing separating it into noncircular compartments each to slidably receive one of said condenser units, and said condenser units being of similar form; so as to be non-revolvable in their respective compartments.

4. In the construction specified in claim 1, said casing being round, and partitions within said casing separating it into segmental form compartments each to slidably receive one of said condenserunits and said condenser units being of similar segmental form in cross section each complete in enclosed package form.

5. A power filter condenser unit comprising an elongated closed container enclosing the condenser elements and provided with exposed contact terminals atone end, said container being three-sided and in cross section of the form of a segment of a circle.

PETER A. TARR. 

